Published on in Vol 7, No 6 (2018): June
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/10468, first published
.
1 Center for Health Policy Science and Tobacco Research, RTI International, Berkeley, CA, United States
2 Center for Health Policy Science and Tobacco Research, RTI International, Research Triangle Park, NC, United States
*all authors contributed equally